Didn't Worf get back home in "Parallels" by finding his carrier wave thingy? I think Spock can get home and chooses not to. The fact he didn't cease to exist after Vulcan's destruction makes me believe he's not connected to his timeline anyway. I agree with King Daniel Into Darkness
, he's just more useful where he is.
Green Shirt wrote:
Click you heels and repeat after me - "There is no place like home".
Dorothy: "You mean you could have told me that before I battled a witch!?!